The invention relates to an apparatus for performing ophthalmic procedures on a patient's eye.
One type of apparatus used to perform an ophthalmic procedure on a patient's eye is a keratoscope, which generates images of a patient's eye. In use of a keratoscope, the patient is positioned to look into the device, which must then be accurately positioned with respect to the patient's eye along a Z axis (which is defined as a line that essentially passes out of the center of the pupil into the device) and X and Y perpendicular axes (extending sideways and up and down with respect to the Z axis). A keratoscope projects illuminated concentric rings onto the cornea, and the appearance of the rings in an image of the eye along the Z axis is used in determining the topography of the patient's eye. Once determined, this information can be used for correctly fitting contact lenses to the patient, for corneal transplant surgery, disease detection, as well as several other medical uses.